Effect of pruning and application of KNO3 + MKP fertilizer on the generative development of several varieties of grapes (Vitis vinifera L.)

Abstract

Research on grape cultivation is still rarely carried out in Indonesia (Tropical Countries) unless it is carried out by Research Centers, which are indeed engaged in developing grapes. This study aims to examine the effect of pruning and application of white Potassium Nitrate (KNO3) and Mono Potassium Phosphate (MKP) on the development of the generative phase of several grape varieties. The study used a completely randomized design (CRD) with two factors, namely varieties (V1: Taldun, V2: Akademik, and V3: Jupiter), and several combinations of fertilizers (P1: KNO3 1 g/L + MKP 3 g/L, P2: KNO3 2 g/L + MKP 5 g/L, and P3: KNO3 3 g/L + MKP 7 g/L). Observations were made on post-pruning bud sprouting time, percentage of buds that produced flowers, percentage of flowers turning into fruit, fruit size (diameter), and total soluble solids (°brix). The data revealed that pruning treatment followed by fertilizer application of KNO3 3 g/L + MKP 7 g/L accelerated the generative phase and produced better fruit quality and quantity for the Jupiter variety.